The Modeling Of Diagenesis And Porosity Prediction In Shuangqing Area Of Liaohe West Sag

On the base of predecessors'findings of diagenesis, the article has pefected the diagenesis numerical simulation and prognostic diagenetic facies oftware system, and completed the diagenesis numerical simulation and the prevision of diagenetic facies in the territory of ShuangQing in The west of LiaoHe sag. The sediment microfacies and diagenesis have an effect on porosity, which is integrative considered in this article. Also, the author have established the correlation model of the reservoir porosity with different sediment microfacies and diagenesis indices, and forcasted the reservoir porosity and ascertained the distribution of valid reservoir. The research has manifested that the principal forming time of oil-gas reservoir of each interval have a closely relate to each other to the diagenesis, and different horizon correspond to different time and order of forming researvoir. The oil-gas reservoir began to form extensively when Es1 entered mid-diagenetic stage A2 substage in Es4, the Es3 main age of forming hydrocarbon-bearing pool was on Es1～Ed, while Es1 and Es2 that age was during the time of Ed～nowadays.Each layered diagenesis intensity represents the trend that the intensity become enhance gradually, and the layer upgrowths regularly a series of diagenetic facies with the increase of diagenesis intensity from the fringe of sag to the center (I.E. from NW to SE in the sag). At highly asymmetrical logitudinal, the diagenetic stage of same territory crescendos from the top to bottom,taking turns to develop certain diagenetic facies.The diagenesis of Es1 reservoir is relatively poor in ShuangQing territory, and porosity of the whole district reservoir greater than porosity cutoff(5.8%)of industrial gas reservoir,all ore mass is effective reservoir; Only does porosity of a small part of area in sag is lower than 5.8%,the porosity of other area in Es2 exceed 5.8%,and both effective reservoirs for oil and gas and valid gas reservoir cover the proportion of about 50% in full regional; Es3 develops the valid oil-gas reservoirs in which the porosity is over 5.8% only in ramp region, and the area is approximately 30% work area. the diagenesis in Es4 is most intensive ,there is effective oil gas, valid reservoirs for oil and gas and gas reservoir only in the north of work area, the area is about a quarter of full section.